Ace the Rust Interview

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beginner · order 45

#[non_exhaustive] for API evolution

enum-nonex-01Related book chapters: 2, 7 (optional — this page is complete on its own)non_exhaustive

Slug: enum-nonex-01 · Paired reading: Chapters 2 and 7

Prompt

#[non_exhaustive] pub enum ApiEvent { Start, Stop } and fn describe(e: ApiEvent) -> &'static str with explicit Start/Stop arms plus _ => "unknown" so future variants do not break callers.